The present invention relates to a semiconductor device and a manufacturing method thereof, particularly to a technique effective when applied to a semiconductor device having a wire for connecting a semiconductor chip (pellet) with an external connecting terminal and a manufacturing method thereof.
It is necessary to take out inputs and outputs of electric signals in order to allow an IC (Integrated Circuit) chip to function. For this purpose, usable is a packaging method of connecting the bonding pad portion of the IC chip with an external lead terminal of lead frame or the like with a gold wire (bonding wire) and then sealing the IC chip and gold wire with a resin.
For example, disclosed in Japanese Patent Application Laid-Open No. Hei 1(1989)-215030 is a technique of preventing cracks (14) appearing at the lower part of the bonding pad of a semiconductor device, which has been obtained by connecting a semiconductor pellet with a lead frame via a connecting wire and then sealing with a resin, by adjusting a ratio (t/S) of the thickness (t) of the ball portion at the tip of the wire to a bonding width (S) at 0.2 or less.